In the field of X-ray examination there is oftentimes a great need to view an object such as an organ of a patient as a three-dimensional image. Such need is particularly acute in angiography. In the past, only single direction radiography has been available as an examination tool in the treatment of congenital heart disease, valvular heart disease, hepatic artery disease, or the like. In the treatment of all of these diseases cardiovascular angiography is employed. However, three-dimensional organs and tissues can be observed only in a single plane when single direction radiography is used. It is extremely difficult to view a single direction radiographic image as a stereoscopic image.
Dual direction radiography has been used in the past to observe the cardiovascular system. Since the two resultant images, however, are both individual planar images differing only in radiographic direction, stereo-viewing of dual direction radiographic images has not proved satisfactory.
Also, in cardiovascular angiography, X-ray fluoroscopy has been performed by injecting a contrast medium and then filming fluoroscopic images with a cinecamera. Since conventional fluoroscopy systems are constructed to use one individual X-ray tube and one individual cinecamera for each direction of radiography, the resultant images in each direction are merely individual planar images even when two-directional radiography is employed. Because of the shortcomings of radiographic and fluoroscopic systems, it is difficult to observe the cardiovascular system precisely in a three-dimensional manner.